The invention concerns the supply of electrical energy to electrical equipment carried by a rotary support. In particular, the invention relates to the supply of electrical energy to electrical equipment carried by a rotor of an aircraft engine.
It is known to equip the blades carried by a rotor of an aircraft engine with a de-icing device, comprising heating resistances intended to prevent the formation of ice. To supply power to said de-icing device, electrical energy must be transmitted towards the rotor.
For this purpose, typically a brush device is used. However, brush devices are generally little reliable and subject to rapid wear. They therefore require regular maintenance. In addition, they are generally heavy and cumbersome and may give rise to problems of compatibility with surrounding oils.
It is also known to transmit electrical energy towards the rotor via a rotating transformer. When the power to be transmitted is high, a rotating transformer is generally a heavy, cumbersome device. In addition, it must be supplied by a source whose power corresponds to the power required by the rotor. A power converter and an energy source sized to deliver high power are therefore necessary.
Additionally, it is known that an asynchronous machine is able to function as a self-excited asynchronous generator. An asynchronous machine typically comprises a rotor comprising a closed electrical circuit (squirrel-cage rotor or windings connected in closed circuit) and a stator comprising at least one winding able to be connected to a load. To allow functioning as a self-excited asynchronous generator, a capacitor bank intended to supply reactive power is connected to the asynchronous machine.
When the rotor is driven in rotation, and if the capacity value of the capacitor bank is suitably chosen in relation to the load and speed of rotation, said asynchronous machine is able to function as a generator and to supply electrical energy to the stator load.